align percentage column in ledger payments

[jkup]

• Submitted a ticket for my issue if one did not already exist.
• Used Github auto-closing keywords in the commit message.
• Added/updated tests for this change (for new code or code which already has tests).
• Ran git rebase -i to squash commits (if needed).

Fix #5402

Auditors @bradleyrichter @srirambv

Test Plan:

1. Open Preferences > Payments
2. Enable Payments
3. Browse websites until you have entries in the ledger table
4. Make sure the % column items are right aligned

[bbondy]

thanks!